Blog
By Siavash Ghanbari ยท Founder of Emojar
๐ฒSix Probability Myths and the Math That Breaks Them
Does a 1-in-100 chance happen within 100 tries? Do two 50% chances make a sure thing? Six common beliefs about odds, checked with real numbers.
Tool GuideCalculatorsMathProbability๐ท๏ธStacked Discounts Explained: A Shopper's Checklist
25% off plus an extra 10% isn't 35% off. Learn how stacked discounts really work, how to work out sale prices, and a checklist for spotting real deals.
Tool GuideCalculatorsShoppingMoneyโฑ๏ธTimesheet Hours Checklist: Breaks, Night Shifts, Decimals
Why 7 hours 45 minutes is 7.75 hours, not 7.45. A practical checklist for calculating shift lengths, unpaid breaks and overnight hours on timesheets.
Tool GuideCalculatorsTimeWork๐ What a $400,000 Home Really Costs Each Month
A worked mortgage example: principal, interest, property tax, insurance and PMI on a $400,000 home, plus what 10% vs 20% down and $200 extra a month change.
Tool GuideCalculatorsFinanceMortgages๐What Score Do I Need on My Final? A Worked Example
Walk through a real course gradebook to find your current weighted grade and the exact final exam score you need for an A, B or C, with the formula.
Tool GuideCalculatorsEducationGradesโ๏ธWhat Your BMI Tells You (and What It Misses)
BMI is a quick screening number, not a verdict on your health. Learn how it is calculated, what the WHO categories mean and when BMI is misleading.
Tool GuideCalculatorsHealthExplainer๐งพWhy Subtracting 20% Doesn't Remove 20% VAT
Taking 20% off a VAT-inclusive price gives the wrong net amount. Here's why, how to remove VAT correctly and how to fix other common VAT mistakes.
Tool GuideCalculatorsFinanceTaxโ๏ธWhy Your "Days Between Dates" Count Is Off by One
Counting days between two dates gives different answers depending on whether you count nights or days. How to get the number you actually need, with examples.
Tool GuideDate & TimeDatesCalculatorsxโฟWhy Your Exponent Answer Looks Wrong, and How to Fix It
Got 1.9999986 instead of 2, an error for a negative base, or "Too large to display"? Here is what each exponent result means and how to get the answer you want.
Tool GuideCalculatorsMathTroubleshooting๐นWhy Your ROI Number Looks Wrong, and How to Fix It
A 45% return can mean 13% a year or 6% a year. Seven common ROI mistakes, from ignoring time and fees to short holding periods, with worked fixes.
Tool GuideCalculatorsFinanceInvesting๐5 Percentage Increase Myths That Trip Up Smart People
Why doesn't a 50% rise followed by a 50% drop get you back to where you started? Five common percentage-change myths, debunked with simple numbers.
Tool GuideCalculatorsMathFinance๐คฐHow Pregnancy Due Dates Are Calculated, With Examples
Why pregnancy is counted from your last period, how cycle length, conception dates and IVF transfers change the math, and what your milestone dates mean.
Tool GuideCalculatorsHealthPregnancy๐ฅHow Big Should Your Calorie Deficit Be? Picking a Pace
Compare 0.25, 0.5 and 1 kg per week goals with real numbers, see why calorie floors exist, and choose a macro split that fits how you like to eat.
Tool GuideCalculatorsHealthNutrition๐How GPA Is Calculated, and How Much You Can Raise It
See how credit hours weight your GPA, work through semester and cumulative examples, and find out what semester GPA you need to reach a target.
Tool GuideCalculatorsEducationGPAโ๏ธPercentage Change vs Percentage Difference: Which One to Use
Percentage change and percentage difference give different answers for the same two numbers. Learn when to use each, with worked examples, zero and negatives.
Tool GuideCalculatorsMathExplainer๐งฐEveryday Money Math: Loans, Savings, Tips and Prices
Compare loans, grow savings, split a bill, check a sale price, find the cheaper pack and sanity-check BMI or calories, with worked examples you can follow.
Tool GuideCalculatorsPersonal FinanceEveryday Math๐งฎWhy Calculators Disagree: Order of Operations Explained
Is 2^3^2 equal to 64 or 512? Why is -2^2 negative? Learn the precedence rules a scientific calculator follows and how to type expressions it reads correctly.
Tool GuideCalculatorsMathExplainer๐How Exact Age Is Calculated in Years, Months and Days
Why is age counted in calendar months, and what happens to someone born on January 31 or February 29? A clear look at the method behind exact age.
Tool GuideCalculatorsDatesExplainer๏ผ How to Calculate Percentages: 7 Everyday Examples
Three percentage formulas cover almost every real question, from test scores to rent hikes. Here's which one to use, with worked numbers for each case.
Tool GuideCalculatorsMathHow-to